Na I just cannot get this to work. It is saying I have an invalid config and won’t boot emulation station now. I have reverted to my previous config. Below is how I edited the config file. I edited it just like yours, or so I thought!
<fullname>PC Engine SuperGrafx</fullname>
<extension>.pce .PCE .zip .ZIP</extension>
<command>/opt/retropie/supplementary/runcommand/runcommand.sh 0 _SYS_ pcengine %ROM%</command>